EP Equipment CQD16, Service Manual

Page: 124 / 251

REV. 07/2016
ELECTRICAL SYSYTEM
8
110
Visual Inspection
-
-
-
Check the surface and appearance of contac-
tor;
Visually check the surface of contactor for
scratches, damages and stains;
If any of the above case is found, please
replace with new contactor.
8.3.3 Checking and Testing
Coil Checks
-
-
-
Disconnect the cables on the contactor;
Check the resistance of the coil with a multi-
meter: measurement method is as shown in
Figure 20508;
Identify if the contactor is normal according to
the readings of resistance on the multimeter.
As shown in the following table:
Resistance
Measurement
Judgment
Approx. 145 Ω Normal
0 Ω
Coil shorting
(replace the contactor)
∞ Ω
Coil breaking
(replace the contactor)
Contact Checks
-
-
-
Check if the surface of contact surface is
smooth and symmetrical;
Separately provide the contact with a voltage
of 48V to observe if the contact can absorb;
If the surface is uneven or the contact does
not absorb, replace the main contactor.
8.3.4 Control Circuit Troubleshooting
Main Contactor Control Circuit
(Figure 90510)
Check if the circuit is broken by using a multi-
meter:
-
- Set the multimeter to ON-OFF;
Check if #45/#46 circuit (circuit between
contactor and drive controller) is conducted.